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CrossOver Brings QuickTime Movies to Linux: Part 2
Pages: 1, 2

HTTP download vs. RTSP streaming

If you're not already familiar with QuickTime on the Web, you might not realize that this technology grabs content in two very different ways. I think it's important to understand the distinction between the two types because they each have advantages and disadvantages.

Screenshot.
CrossOver enables QuickTime 5 playback for the Linux platform.

Until QuickTime 4, HTTP download was the only the only method for accessing QT video on the Web. Authors would compose their multimedia and place the .mov files on an HTTP server. Users would click on the files via their browsers to initiate the download process. Once the files were safely captured in the browser's cache, they could be played in their entirety without interruption. They could also save files to disc for viewing later.



In order to let you begin to watch the movie before you finish the download, Apple engineers developed the "Fast Start" technology. You enable it by setting your plug-in preference to the bandwidth you have available. During HTTP download, the application uses that setting to determine how much of the movie it has to download before it can start playing it without interruption. This gives the feeling of "streaming" even though technically it isn't -- it's just starting fast.

Fast Start allows the convenience of streaming, but with the option to save the video to the hard drive -- a luxury not available with true streaming video.

When QuickTime 4 was released, we had the option to watch video via the plug-in or player via true RTSP streaming, similar to the technology that RealNetworks has used for years.

RTSP is true streaming that begins playback as soon as the link is negotiated. It requires a streaming server. And the content can't be saved to the hard drive. RTSP is also more vulnerable to network congestion and interruptions than HTTP serving.

RealNetworks has worked hard to improve its technology to prevent playback disruption, but Apple didn't introduce its "skip protection" until QuickTime 5, which is the version that CrossOver installs on your Linux machine.

In my opinion, the user experience is still better with HTTP serving that with RTSP. If you're new to QuickTime, I'd experiment first with the HTTP downloads on the Movie Trailers page. Once you get a feel for how your machine and bandwidth combination handles this type of rich content, then you can decide if you want to try streaming via QuickTime TV and other streaming sources. Most of the QuickTime content on the Web today is the HTTP variety.

QuickTime Pro for authoring?

The QuickTime player and browser plug-in are free on all platforms. But for those who want more advanced functionality and authoring tools, Apple offers QuickTime Pro for $29.99 USD.

What's interesting about this is that when you install standard QT, you have acquired all of the pro goodies too. The reason you pay Apple 30 bucks is for a pro key that "unlocks" all of those tools that you already have.

In my testing, I wanted to push the CrossOver plug-in as far as possible, so I purchased a pro key and upgraded my "Linux" version of QuickTime. The thought of being able to author QuickTime content on a Linux box was almost more excitement than I could bear.

Some of the basic goodies that you get with the pro version are:

  1. Looping: Allows you to play a movie in a continuous loop. Great for annoying visitors at tradeshows.
  2. Save movie to disc: Provides a handy drop-down menu that enables the "save to disc" function for any HTTP-served content you view, unless that is, the author has blocked that function.
  3. Editing of content: Enables the cutting, copying, pasting, trimming, adding, and deleting of audio and video tracks. Using these tools allows you to take bits of QT content and make your own movie.
  4. Image sequencing: Creates online slideshows by simply choosing a directory of pictures and setting a few basic parameters.
  5. Present movie: Gives you the option of presenting QT content against a black screen with no visual distractions.

Here's where the CodeWeavers developers still have a little more work to do. Your QT pro key, when applied to the CrossOver installation of QuickTime, only enables enhanced functions number one and two from my list above. Items three, four, and five are simply not present.

If you check some of the drop-down menus in the CrossOver installation of QuickTime with the pro key enabled, you'll see that certain items are duplicated, such as "copy" followed by another "copy." Well, neither copy works because the selection tools aren't enabled. Another function is supposed to be located where the second "copy" appears.

So the question is, is it worth spending $29.99 for the pro version when all you get is the save function and looping? For most folks probably not. But if you already have a QT 5 pro key for Windows, there's no harm in using it with CrossOver to enable the couple extra goodies.

Final thoughts

I am truly impressed with the basic QuickTime functionality that CrossOver brings to the Linux platform. On a decent mid-level computer, the download and playback of multimedia content is virtually the same as it is on QuickTime's native platforms. Now Linux users can watch the latest online spoofs and newsclips without having to switch to a Macintosh or Windows PC.

I did trip over a couple of minor annoyances. The one that bugged me the most was that the movie title didn't display properly at the top of the player. But generally speaking, these annoyances were rare and didn't affect my enjoyment of watching movies.

I liked that all of the metadata associated with the files was displayed properly in the correct locations (except for the movie title, that is). This means that descriptions, copyright information, and credits were accessible to Linux users just like they were on other platforms. Plus all of the movie properties, such as frames per second, codec type, and data size, were also available.

My request for future improvements centers around enabling all of the authoring tools in the pro version. QuickTime is potentially a great multimedia tool for open-source artists. Because it handles not only .mov files, but also nearly every other audio and video type -- including MPEG-4 very soon -- Linux users are able to work in the format of their choice with one tool. If that doesn't embody the open-source way of thinking, then what does?

If you are interested in playing rich media on your Linux box, I recommend that you buy CrossOver. Once you've paid your money and used the product, let them know that you want them to add the pro functionality that will make it a full-fledged citizen in the QuickTime community.

Derrick Story is the author of The Photoshop CS4 Companion for Photographers, The Digital Photography Companion, and Digital Photography Hacks, and coauthor of iPhoto: The Missing Manual, with David Pogue. You can follow him on Twitter or visit www.thedigitalstory.com.


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